Cylinder lock



Dec. 3, 1935. P. w. oLsoN CYLINDER LOCK Filed Feb. 2e, 1934 Plantea D. 3,'193s L. UNITED STAT-Es- PATENT otr-*lcs to Automatic Musical Instrument Company,

61199185111@ Mich, corporation ofllichixln Appliesum rem 26,' 1934; sei-ni Np. '113,001'

of a lock which is less susceptible to being damaged by jimmying o r attempted forcible operationathan the prior types of locks. 1 In the more common constructions of cylinder locks, the series of key-operated tumblers project, from the plug into. recesses inthe barrel of the lock, and the tumblers directly prevent the rotation of the plug. Accordingly when a flat instrument such as a screw driver is inserted in the keyway in an attempt to forcibly rotate the plug-by shearing the tumblers, the tumblers are likely to be damaged even if the jimmying is ul, somuch so that'the lock can no longer beoperated by the proper' key.

In this invention the rotation. oi

when forcible rotation is'attempted the tumblers -are not affected and the lockis less apt to be materially damaged'.

. Other objects and advantages of this invention will become more apparent in the following description, taken vwith reference to the ,acconf panying drawing, in which an illustrative embodiment-of the invention is shown. L

" Fig. l isa longitudinal section of'a cylinder.

lock unit with plu'g shown in full, and theparts vin normal and-locking position. 2 is asimilar v iew with a' keylinserted andd the plug unlocked and freed for rotation. Fig. 3 is a rear elevation lookin from the left atrial.'

Fig: 4` is 'plug removed, takexifoizlA the line 4 4 of,Fig. 3.

Fig.Y 5V is a front elevation of 'the'lock unit. Figs- 6 is 'a section taken on the line 6-6 oi Fig; 1. f v Fig' is a cross-section ,of theplug, taken'on the line 'll 'of Fig.. l.- x Y 8 is a plan view of the plug removed from the barrel, looking down on'Flg. 1, with parts shown in section and parts shown in-elevation.

Fig. 9 is a front elevation-of the plug removed -1froin thebarrel.

Fig .10.is a per tive view of one of the tumblers.f -A barrel Il is provided. which is substantially 50 tubular in 'formatioin .and is adapted to be threaded into a lock assemblage, the barre being iixedly'secured in position; and a plug I con-- tained in the barrel may be provided with any common arrangement, such as an eccentric lug i il on the rear and end thereof,'for opera.

'bvl onpositely the plugjn Y- locking position is opposed by-snrfaces integrally Y formed on. the plug and in the barrel so that a sectin er the lock' 'ban-e1, with-the that, by the 'insertion s, om wl. flo-4s) lI-'his invention relates to improvements cylinder locks, and more especially to the'provision tive engagement with the movable lock elements. vA key-hole plate: I l is mean secured in the front end'of the bore ofthe barrel; and at vthe rear end the bore is' enlarged to provide a shoulder v l5 for' limiting the forward movement -of 5.*

theplugjand is grooved at i1 for'retaining a curv'ed plate-spring, which urges thev plug forwardly- .The medial portion of the bore of the barrel is provided with a plurality of spaced annular lo grooves I9, leaving ridges 20. which arenotched f longitudinal grooves 2l, which intercept the annular grooves,l A l 'A' simple vform ofbuilt-up constructions for the plug is shown, which makes the machiningoperal5 I i.

tions quite simple and providesa'n accurate construction' suitable fdr high grade locks of material, such as brass, which lasts indennitely without appreciable wear, and is not subject to corrosion which would in time interfere with the opr- 20 ation ofthe lock.. a

' VA pair of cylindrical segments 2 2 are provided,

which are spaced by a pair of bars 23 to provide the lxeyway 2l, as best' shown in-Fig, 7. At the ends the segments andliars are fastened together 25 by meansof discsA 25 and 26, 'the discsbeing re- Vcesse'd to receive reduced circular end portions 21 'of the segments, and apertured'fer receiving reduced end staking portions 28 of the bars, which' v project The plate 25 on the front end offthe plug isof even' diameter with the plug;` and the, disc v26 at the rear endis'enlarged toabut against the.

shoulder i5 to limit the' forwardimovement of the plug. The plug is pressed forwardly into locking position by said spring I8, so that the oppositely disposed row of lugs 30, integrally formed on the surfaces of the segments 22, then` are in registration with `the ridges 20 and engagesin the notches to opposefth'e rotational move- 40 ment of the lock. I A The plug is locked in the forward position by a series of plungers 3|, which are slidably mounted in the plug, at either side of the keyway.Y The tumblers are in staggered relationwith` the lugs, 45

and, thereo're,.in the locking condition, project -into the grooves i9 4and abut against the sides ofthe ridges 2t. Projecting into the/key'wayare lugs 32 formed on the respective tumblers, so

of an. irregularlyflgrooved 50. key V33, the ends of the tumbler-'s may be withdrawn into the plugtot-release the plug for end-- wisemovement. Thenfby'pressing onfthe key, the plugmay'be shoved into the barreLs'o that f the locking lugs 3i register with the grooves [55 through and are iriveted over the plates. 3Q.

- missible clearances, and lack of lubrication, the

tumblers are apt to stick in the slots in the plug andwork very stiff, and it is found that by reducing the area of the Vsurfaces in contact, as by grooves 34 the tumblers operate freely with little friction. i

It is now manifest that, in locking condition, the rotation of the plug is opposed-entirely by the solid lugs 30 formed on the surface of the plug in contact with the sides of the notches 2| formed in the ridges in the bore of the barrel, and no strain is placed on the tumblers in an attempt to forcibly rotate the plug, since the tumblers are free to rotate in the grooves. The solid lugs will resist a heavy shearing pressure, and will withstand much deformation without interfering withsubsequent operation of the lock with a proper key.

Incase that some one familiar with the construction of the lock should attempt to drive the plug in, the shearing strength of the tumblers is greater in resisting endwise movement of the plug than in resisting rotational movement.

Having thus described. my invention, I claim: 1. A lock comprising a barrel, a plug movably mounted in the barrel, projections integrally formed in the bore of the barrel and on the surface of the plug whichinterengaged to prevent rotation of the plug when the plug is in a locking position, and tumblers mounted in the plug for holding the same against longitudinal movement in said locking position vbut not opposing the rotation of the plug, the tumblers being operable by the insertion of a key for releasing the plug for longitudinal movement -to disengage said projections so that the plug may then be` rotated.

2.l In a lock having a barrel having a cylindrical bore, a cylindrical plug inserted in the bore, means for locking the plug in thebore comprising cooperative and interengaging recesses and surfaces'integrally formed in the bore of the' barrel and on the surface of the plug for locking theplug against rotation arranged so that when the plug is shifted endwise it is' free to rotate, the bore having circumferential grooves and the plug having` key operated movable tumblers for locking the plug against endwise movement 3. In a lock, a tubular barrel having annular grooves formed in the bore thereof, the ridges lbetween the grooves being notched, a plug inserted in the bore of the barrel, the plug having lugs integrally formed on the surface thereof for engagement in the notches to prevent rotation, and key operated tumblers contained in the plug releasably engageable in the grooves to prevent longitudinal movement of the plug.

4. In a lock, a tubular barrel havingpannular grooves and longitudinal notches intersecting the grooves formed in the bore thereof, a plug inserted in the bore. the plug ha'ving lugs integrally formed on the surface thereof for engagement in the notches to prevent rotation of 5 'the plug, and key operated tumblers mounted in the plug for engagement in xthe grooves to prevent longitudinal movement of the plug arranged so that by inserting a key and withdrawing the tumblers the plugmay be moved endwise .to're- 10 lease the lugs from the notches to permit rotation of the plug for unlocking.

5. A composite cylinder lock plug comprising two oppositely disposed cylindrical segments spaced by two longitudinally extending bars to 15 form -,a central keyway, and end members for l fastening said segments and bars together comcomprising a pair of cylindrical segments spaced by a pair of longitudinally extending bars to vform a cylinder with a central keyway, the end portions of said segments and bars being reduced in cross section, and discs recessed to' re- 25 ceive said reduced end portions for bindingJ said parts together.

7. A built up cylindrical lock plug comprising a pair of cylindrical segments, a pair of longitudinally extending bars for spacing the seg- 30 ments to form a keyway, the inner surfaces of the segments being slotted to provide tumbler slots at either side of the bars, and recessed discs engaging the ends ofthe segments and bars to bind them together. Y 35 8. In a lock, the combination with a tubular barrel having annular grooves in the bore and notches in the ridges between the grooves, of a plug insertable in the bore having integral lugs extending therefrom 'for engagement in the 40 notches to prevent rotation, key voperated tumblers in the plug releasably engageable in the grooves to prevent longitudinal movement of the plug to disengage the lugs thereof, and a spring between the barrel and the plug tending to press 45 the plug longitudinally for engaging the lugs with the ridges to prevent rotation of the plug.

9. A lock comprising the combination of a barrel having annular grooves therein and the ridges between the grooves being notched, a plug insertable in the barrel having intqral lugs extending therefrom i'or engagement in the notches to prevent rotation, Vkey operated tumblers in the plug Areleasably engageable in` the grooves to prevent longitudinal movement of the plug, and a bowed spring having its ends in an end groove of the barrel and its median portion engaging the rear of the plug and tending to press it longitudinally forward for engaging the lugs with the notches. 

